Chemical and Biological Differentiation of Cortex Phellodendri Chinensis and Cortex Phellodendri Amurensis

The Chinese herbal drug Cortex Phellodendri is derived from two species of Phellodendron, P. chinensis Schneid. and P. amurense Rupr. Traditionally, Cortex Phellodendri Chinensis (CPC) and Cortex Phellodendri Amurensis (CPA) are used interchangeably because they are believed to share the same clinical efficacy. Berberine has been believed to be the active ingredient of the herbs. However, recent studies have shown that the content of berberine is much higher in CPC than in CPA. Interestingly, the majority of researches deal with CPA, the one with lower content of berberine. These observations provoke us to reconsider the active ingredients of Cortex Phellodendri. In this study, two traditional usages (antidiarrheal and antibacterial) of Cortex Phellodendri were compared with the chemical analysis of the two herb species used in its formulation. The results suggest that berberine is one of the active ingredients responsible for the antidiarrheal and antibacterial activities of the herbs, but that other chemical ingredients are also involved in regulating the biological actions of the herbal drug. These chemical ingredients may have the same or the opposite effect as berberine. The effectiveness of the herbs is more likely to correlate to the content of total alkaloids rather than to the content of berberine.